Recent investigations with focus on regeneration of the periodontium have studied various systems which attempt to define specific factors involved in the formation of a new connective tissue attachment. Essential biological events involved in wound healing are chemotaxis of a multitude of different cell types and subsequent proliferation and survival of a limited number of specific cell types. Extracellular matrix proteins and various polypeptide growth factors have been shown to stimulate both chemotaxis and proliferation in different systems of wound healing. However, no periodontal ligament cell specific factors have as yet been isolated. Here we propose to isolate and characterize a polypeptide found in conditioned media of PDL cells that appears to be a specific chemoattractant for PDL cells and also for cells of osseous origin. In addition, using the purified chemoattractant we will examine the role that this polypeptide plays in stimulating PDL cell chemotaxis in conjunction with other biological response modifiers. Finally, we will isolate and identify specific PDL cell surface receptors for this factor. Initial purification of the factor will be accomplished by conventional (NH4)2SO4 precipitation of PDL cell conditioned media followed by open column chromatography, affinity chromatography and high pressure liquid chromatography. Antibody to the polypeptide will be raised. The PDL cell surface receptor for the PDL chemoattractant will be isolated by affinity chromatography. Biological response modifiers including FGF, ECGF, PDGF, TGF-beta and the extracellular matrix components FN, LM will be examined for their contribution to PDL chemotactic factor induced PDL cell movement and proliferative responses.